Sciatic Nerve Block

I. Posterior Sciatic Nerve Block



Indications:
In combination with the 3 in 1-block, all operations on the lower limb
Special Contraindications: none
Landmarks::
Posterior superior iliac spine1, greater trochanter2
Puncture site:
3 cm below middle of line joining 1 & 2
Insertion of needle:
Introduce the needle vertical to the skin 6-8 cm deep
Dosage:
20-30 ml 1 % lignocaine or prilocaine or 0,5% bupivacaine


II. Anterior Sciatic Nerve Block

Landmarks:
Inguinal ligament1, greater trochanter2
Puncture site:
At the point of intersection of a line from the junction of the middle
third and the medial third of the inguinal ligament with a line parallel to
the inguinal ligament at the greater trochanter level
Insertion of Needle:
Slight lateral direction to contact the femur, retract the needle to the
subcutaneous area and correct the direction until the needle slides
off the femur, then push forward approx. 5 mm
Dosage:
10-20 ml 1% lignocaine or prilocaine or 0,5% bupivacaine


3 in 1-block

The lumbar plexus is "sandwiched" (Winnie) between the psoas major m. and the quadratus
lumborum m. and enveloped by their sheaths
Local anaesthetic runs up from the injection site and blocks the femoral n., the lat. cut. n. of
thigh and the obturator n.
Indications:
In combination with sciatic nerve block, all operations on the lower
limb
Special Contraindications:
none
Landmarks:
Inguinal ligament2, femoral a.1
Puncture site:
Below the inguinal ligament, 1-1,5 cm lateral from the femoral a.
Insertion of Needle:
In slightly cranial direction
Dosage:
25—30 ml 1 % lignocaine or prilocaine or 0,5% bupivacaine